Volume 58 – Issue 4 (Dec 1993)

Cardamine impatiens L. and Sibara virginica (L.) Rollins have little in common save being weedy annuals of the Brassicaceae tribe Arabideae. Cardamine impatiens is erect, to eight dm, with linear siliques and wingless seeds. It grows in shaded, alluvial habitats and blooms and fruits from mid-May to mid-June. Sibara virginica has a spreading habit, seldom above two dm in height, and has flattened siliques with winged seeds. It is found in moist, sunny openings and blooms and fruits from mid-April to mid-May. Cardamine impatiens is of European origin and is established over much of the northeastern United States from New Hampshire west to Michigan and south to West Virginia (Al-Shehbaz 1988). Sibara virginica is indigenous to the southeastern United States and ranges from Florida to Texas north to Virginia, Ohio and Kansas, with disjunct populations in California and Baja California (Weishaupt 1971, Al-Shehbaz 1988).

Over a decade of study reveals that the vascular flora of the James River Gorge watersheds between Snowden and Glasgow, Virginia, including portions of the James River Face Wilderness, and portions of Amherst, Bedford, and Rockbridge Counties is superbly diverse. Voucher specimens document a vascular flora of 468 genera in 119 plant families with 963 taxa in the 3585-hectare research area. Largest collections of the Gorge flora are represented by the Asteraceae (130 spp.), Poaceae (93 spp.), Cyperaceae (61 spp.), Fabaceae (54 spp.), and Rosaceae (41 spp.). Of the species collected, 21% are introduced taxa. The collected taxa are compiled in an annotated list.

New stations for 12 species of vascular plants considered rare, imperiled, or critically imperiled in Mississippi were discovered during collecting trips made from 1984-1989. The study area included two chalk outcrops and barrens, a mesic calcareous bluff, and a small stream bottom at the base of the bluffs along a transition area between the Pontotoc Ridge and Black Prairie physiographic regions for a distance of approximately 2.5 km. All sites are in Oktibbeha County, Mississippi, in the northeastern quarter of the state. The rare, imperiled, or critically imperiled species reported herein, which are usually associated with calcareous soils in Mississippi, are Apios priceana, Carex gracilescens, C. meadii, Carya laciniosa, Dodecatheon meadia, Euonymus atropurpureus, Fraxinus quadrangulata, Menispermum canadense, Nemastylis geminiflora, Panax quinquefolium, Penstemon tenuiflorus, and Swertia carolinien.

The empress tree, Paulownia tomentosa (Thunb.) Steud., is native to eastern Asia and naturalized in portions of the eastern United States. In a central Virginia streamside forest, P. tomentosa trees ranged from 6 to 30 years in age (mean age = 17.1 years). The age distribution of P. tomentosa was unimodal with a strong peak in the 18 and 20 year age classes, demonstrating a major recruitment pulse in the early 1970s correlated with the passage of Hurricane Camille (August 1969). Paulownia tomentosa had the lowest importance value (=15.1) among the four dominant forest trees of the study area (Liriodendron tulipifera = 30.1, Betula lenta = 28.5, Platanus occidentalis = 16.0). Diameter distributions for all major tree species, except P. tomentosa, followed a concave pattern, which is representative of increasing or self-maintaining populations. The diameter and age distributions for P. tomentosa were convex, which indicates episodic establishment. Unlike many exotic woody plants naturalized in forests of the eastern United States, P. tomentosa is noninvasive and functions much as it does in the mesophytic forests of eastern Asia, producing small, scattered populations that arise chiefly as a result of large-scale disturbance.

Do you believe that nearly 700 species of plants may become extinct by the year 2000? Realization that such might be true has caused quite a bit of concern for developers, conservationists, and policy makers caught in between. Scientists and laymen both have increased their research attention to rare species in an attempt to identify, understand, and hopefully preserve them. The term “endangered species” has become a household term, frequently referring to more than just natural organisms.

A 0.4 ha vegetation plot established in 1962 in Albright Grove, an old-growth cove forest in the Great Smoky Mountains, was resampled in 1992. A 0.6 ha plot encompassing the entire 1962 plot area was surveyed, mapped, and permanently marked in 1992. The diameter (dbh) and species of all live and dead tree stems >1.37 m tall were recorded in 10 0.04 ha contiguous plots in 1962, and in 60 0.01 ha contiguous subplots in 1992. Changes in the original 0.4 ha plot area over the 30-yr period are summarized here. The basal area of standing dead trees decreased from 15.7 to 3.5 m2/ha. Castanea dentata accounted for 29% of the original, and 0% of the recent standing dead basal area. Live tree basal area and biomass increased from 47.3 to 57.7 m2/ha, and 386 to 459 Mg/ha, respectively. Total stem density decreased from 642 to 563 stems/ha. Size-class distributions exhibited a gradual, log-linear decrease in stem density with increasing size at both sampling dates. No marked changes in species composition of the tree stratum were observed; Acer rubrum and Tsuga canadensis dominated at both sampling dates. Species-specific, radial growth rate means ranged from 0.7 to 2.2 mm/yr. Mortality rates for all canopy trees >30 cm dbh were in the 0.5 to 1.5%/yr range. Changes in the stand appeared to be driven by small canopy gap dynamics.

Significant progress in the affairs of our Society was made in 1992-93 under the leadership of John M. Herr, Jr. Particularly notable were the adoption of a new Constitution and By-Laws providing specific guidelines for governance of the Society and the establishment of the type-set of our journal, Castanea, at West Virginia University. John, in his capacity as Past-President, continues to serve the Society as Chair of the Planning Committee. In that role, John and members of the Planning Committee are pursuing a number of initiatives to broaden and, concurrently, focus our impact as a society of botanists through the formation of a “Consortium of Botanical Societies.”